This paper presents a case study on an accident that occurred in the interior of a floating production, storage, and offloading vessel (FPSO) in order to verify whether this major accident was related to the loss of technological knowledge. In addition to the accident report study, a broad theoretical background has been elaborated to support the hypothesis that major accidents are related to loss of technological knowledge. The outcome of this study shows that the accident occurred at an FPSO in February 2015 had a direct relationship with the loss of technological knowledge, either in the production processes or in process risk management. With the results extracted in this study, it is intended to contribute to the companies that deal with dangerous processes. This will enhance the awareness of actions that can be taken to avoid the loss of technological knowledge, thus reducing the probability of major accidents. (C) 2017 Elsevier Ltd. All rights reserved.